code: def _test_init(self, cls, **params):
      encoder = cls.from_params(**params)
      self.assertTrue(isinstance(encoder, nn.Module))
  
file_path: mmf/tests/models/test_albef.py
imports: import unittest
  import torch
  from mmf.models.albef.vit import AlbefVitEncoder
  from omegaconf import OmegaConf
  from tests.test_utils import setup_proxy
  from torch import nn
label_desc: Use image node_id 2 for calling the TestAlbefEncoders obj's underlying member method code with example usage: obj._test_init(cls) without return types